These surplus high power PAs using 4 x MRF151 were originally used in watercooled industrial VHF drivers. The devices and some of the other components protrude about 2mm below the PCB lower surface.

To minimise the amount of copper required, I decided to make a heatspreader to go under the devices and make aluminium spacers for the rest. I also decided to make a fixture to hold the spreaders so I could cut neat pockets for the devices. Not sure that was a sensible approach. It certainly meant I had to do some tricky machining.

I have some more to make, I won’t be doing the fancy pockets this time, just transverse slots.

Tony’s 1.2m dish has a figure-8 style extrusion for the feed arm, so clamps need to have two holes and a centre relief. For the new dual-band horn mount, we needed a bit more length, so I made up some extension plugs from aluminium

Someone was asking for advice about hope to connect a tapping point to a big coil made from 8mm copper tube. I came up wiht this solution. The copper hook and brass thumbscrew were made from bits in my scrap bin. There is a hole so a wire can be soldered to the hook.

I wanted to avoid an extra plug/socket on the LDF1-50 coax feed from the 5.7GHz horn to the masthead transverter/PA, so I used a plastic cable gland, but there was still too much movement. This clamp bolts to the inside of the steel masthead box and holds the coax rigidly so I can plug directly into the coax relay without any danger of movement and fracture.

I found a cheap surveyor’s tripod on ebay and made up a new screw and mounting adaptor to fit a short 2 inch stub mast. The original locking screw was trashed.